Iteratively run a Stock Synthesis model with different jittered starting parameter values based on the jitter fraction. Output files are renamed in the format Report1.sso, Report2.sso, etc.
Usage
jitter(
dir = NULL,
mydir = lifecycle::deprecated(),
Intern = lifecycle::deprecated(),
Njitter,
printlikes = TRUE,
jitter_fraction = NULL,
init_values_src = NULL,
exe = "ss3",
verbose = FALSE,
extras = NULL,
...
)
Arguments
- dir
Directory where model files are located.
- mydir
Deprecated. Use
dir
instead.- Intern
Deprecated. Use
show_in_console
instead.- Njitter
Number of jitters, or a vector of jitter iterations. If
length(Njitter) > 1
only the iterations specified will be run, else1:Njitter
will be executed.- printlikes
A logical value specifying if the likelihood values should be printed to the console.
- jitter_fraction
The value, typically 0.1, used to define a uniform distribution in cumulative normal space to generate new initial parameter values. The default of
NULL
forces the user to specify the jitter_fraction in the starter file, and this value must be greater than zero and will not be overwritten.- init_values_src
Either zero or one, specifying if the initial values to jitter should be read from the control file or from the par file, respectively. The default is
NULL
, which will leave the starter file unchanged.- exe
Executable name. Can be just the name of the executable file if it is in the specified directory or in the user's PATH. Can also include the absolute path or a path relative to the specified directory. Needs to be a single character string, not a vector. On Windows,
exe
can optionally have the.exe
extension appended; on Unix-based systems (i.e., Mac and Linux), no extension should be included.- verbose
A logical value specifying if output should be printed to the screen.
- extras
Additional ADMB command line arguments passed to the executable, such as "-nohess"
- ...
Additional arguments passed to
run()
, such asshow_in_console
, andskipfinished
.
Details
This function will loop through models using the default strategy set by the
future
package in the current working environment. In general, this means models
will run sequentially. To run multiple models simultaneously using parallel
computing, see future::plan()
Note that random number generation occurs outside of R directly in stock synthesis.
When running jitters in parallel (i.e. future
strategy is not sequential
), no formal
steps are taken to ensure independence of random numbers generated across
cores. However, when running in parallel, there is a pause of i seconds before the
ith jitter starts. The stock synthesis random number seed is based on the
system time down to the second, so this is intended to produce random numbers
from different seeds for each jitter. Random numbers may still not technically
be considered statistically independent. If jitter results are only used as a
general heuristic for model convergence, this mild lack of independence should
not matter much.
When running models in parallel, the transfer of large files leads to expensive
overheads and parallel processing may not be faster. Covariance files are
especially expensive to transfer, so the option extras = '-nohess'
is
recommended when using parallel processing.
See also
Other run functions:
copy_SS_inputs()
,
populate_multiple_folders()
,
profile()
,
retro()
,
run()
,
tune_comps()
Author
James T. Thorson, Kelli F. Johnson, Ian G. Taylor, Kathryn L. Doering, Kiva L. Oken, Elizabeth F. Perl
Examples
if (FALSE) { # \dontrun{
#### Run jitter from par file with arbitrary, but common, choice of 0.1
modeldir <- tail(dir(system.file("extdata", package = "r4ss"), full.names = TRUE), 1)
numjitter <- 25
jit.likes <- jitter(
dir = modeldir, Njitter = numjitter,
jitter_fraction = 0.1, init_values_src = 1
)
#### Run same jitter in parallel
ncores <- parallelly::availableCores(omit = 1)
future::plan(future::multisession, workers = ncores)
jit.likes <- jitter(
dir = modeldir, Njitter = numjitter,
jitter_fraction = 0.1, init_values_src = 1
)
future::plan(future::sequential)
#### Read in results using other r4ss functions
# (note that un-jittered model can be read using keyvec=0:numjitter)
profilemodels <- SSgetoutput(dirvec = modeldir, keyvec = 1:numjitter, getcovar = FALSE)
# summarize output
profilesummary <- SSsummarize(profilemodels)
# Likelihoods
profilesummary[["likelihoods"]][1, ]
# Parameters
profilesummary[["pars"]]
} # }